Fig. 38.

Cox Multivariate Proportional Hazard Regression model analyzing the combined influence of six predictor variables (gender; age; lipoma type; symptoms; redo versus virgin; and cord-sac ratio) on PFS after total resection, featuring the resultant effect of the three cord-sac ratios of <30%, 30–50%, and >50%. The hazard ratios and p values for all six predictor variables are listed in the miniaturized table, showing that cord-sac ratio exerts the only significant independent influence on outcome. The respective progression-free probabilities, as indicated by the arrows, are 96.9% for low ratio, 86.2% for intermediate ratio, and 78.3% for high ratio. The differences in hazard prediction for the three ratios are highly significant (p=0.0009 in bold). <30%; 30–50%, and >50% indicate the three cord-sac ratios as shown in magnetic resonance imaging insets. Reprinted from Pang [55] with permission from the Japanese Neurosurgical Society. Sym/Asym : symptomatic versus asymptomatic lipomas.